Field of the Invention
Exemplary embodiments of the present invention relate to an underwater docking system for docking a target body on a station under water, and a docking method using the system.
Description of the Related Art
Unmanned underwater vehicles are increasingly used for surveying the sea floor and marine ecological environments, and for surveying characteristics such as water temperature and salinity in areas that exceed the limit to which humans can physiologically dive. Such unmanned underwater vehicles may further be used for work in contaminated areas, or in detecting explosives such as mines and removing them, or in military operations such as underwater reconnaissance. Research on such unmanned underwater vehicles is also increasingly being conducted.
Such unmanned underwater vehicles include autonomous underwater vehicles (AUV), remotely operated vehicles (ROV), and underwater robots, all of which can be autonomously operated under water. It is necessary, however, for unmanned underwater vehicles to be periodically retrieved from the sea for maintenance, such as charging or replacement of a battery after underwater operations.
A lot of time and cost are required to retrieve an unmanned underwater vehicle from the sea. As a method of reducing such time and cost, it is preferable that the unmanned underwater vehicle be docked on an underwater docking station without retrieval onto the ground, and then battery charge and data transmission and reception are conducted in real time with the vehicle remaining under the water. However, it is very difficult to conduct a series of operations including guiding the unmanned underwater vehicle toward the stationary docking station under the water and precisely and reliably docking the vehicle on the stationary docking station. This is because the range of vision underwater is comparatively short, a typical radio communication method cannot be used under the water, and the position of the unmanned underwater vehicle varies due to the tidal current.